The present invention relates to a lawn and garden tool and, more particularly to a portable tool having interchangeable implements which operate at high torque and low speed.
Preparation and maintenance of lawns and gardens has great commercial and homeowner interest. Portable tools for work on lawns and gardens are largely manually operated. In recent years, the use of powered tools has increased especially gasoline engine and electrically powered tools. These tools include lawn edgers, trimmers, cultivators, leaf blowers and hedge trimmers.
In U.S. Pat. No. 4,213,504 Schneider discloses a rotary, hand-held apparatus for performing various soil working operations. The soil working implements selectively include soil engaging tines, auger, drill, etc. The device may employ manual, electrical, gas, etc. power sources and cultivating, mulching, weeding, boring, etc. implements. In one embodiment, an electric drill is secured to a handle to drive the implements. In U.S. Pat. No. 4,293,041 Holmstadt et al disclose a power cultivator with a debris-excluding barrier and scraper, wherein the tillers are counter-rotated and include interdigitating tines which engage and move the earth forwardly. Worm gears on the tillers are driven by a common centrally located shaft mounted worm gears. Rickard et al in U.S. Pat. No. 5,802,724 and Everts et al in U.S. Pat. No. 5,809,653 disclose a coupling for a split-boom power tool having an attachment which may include a hedge trimmer, line trimmer, pruner, blower or extension. The motor directly drives the attachment, there being no gearing therebetween. Lessig III et al in U.S. Pat. No. D 252,879, disclose an electric-powered earth tiller.
In U.S. Pat. No. 2,975,848 Roberts discloses a portable power-driven device for boring holes which has a pinion gear on the power shaft of the motor and a larger driven gear meshing with the teeth of the pinion gear. The driven gear is attached to the shaft of a chuck. In U.S. Pat. No. 4,366,871 Dieterle et al disclose a motor-driven screwdriver, wherein a planetary gear carrier carries a plurality of circumferentially-displaced planet gears meshing with a pinion driven by the motor of the screwdriver. The screwdriver does not have a cascade of planet gears.
There is a need for a portable power-driven lawn and garden tool which has interchangeable implements.
It is an object of the present invention to provide a portable, power-driven lawn and garden tool which has interchangeable implements and the implements are driven at high torque and low speed.
In accordance with the teachings of the present invention, there is disclosed a hand-held portable power driven tool for using a tool implement. A housing encloses a permanent magnet electric motor. The motor drives a planetary gear system having at least two sets of gears arranged in cascade to provide a low speed, high torque output. The output of the gear system drives the tool implement. The motor is powered by at least one rechargeable battery pack, the battery pack being replaceably inserted into the lawn and garden tool.
In further accordance with the teachings of the present invention, there is disclosed a portable, hand-held lawn and garden tool which has a wand having a first end and an opposite second end. A handle is connected to the first end and a housing is connected to the second end. A first set of gears is disposed in the housing, the first set of gears being a sun gear engaging a plurality of planetary gears. A plurality of sets of gears similar to the first set of gears are provided, the sets of gears being connected in cascade to an output shaft. A plurality of implements are provided. A selected one of the implements is removably attached to the output shaft connected to the cascade of sets of gears, wherein the respective implements are interchangeable. Means are provided for driving the sets of gears connected to the sets of gears such that the selected implement is driven at a selected high torque and a selected low speed dependent upon the arrangement of the plurality of sets of gears.
Also in accordance with the teachings of the present invention, there is disclosed a portable lawn and garden tool. The tool has a wand having a first end and an opposite second end. A handle is connected to the first end. A motor in a housing is attached to the second end. A source of power is provided for the motor and a switch is disposed in the handle to control the power to the motor. A first set of gears is attached to the motor within the housing. The first set of gears is a sun gear engaging a plurality of planetary gears. A plurality of sets of gears similar to the first set of gears is provided, the sets of gears being connected in cascade. A plurality of implements are provided, a respective one of the plurality is removably attached to the cascade of sets of gears. The respective implements are interchangeable. The implement is driven at a selected high torque and a selected low speed depending upon the arrangement of the plurality of sets of gears.
Still further in accordance with the teachings of the present invention, there is disclosed, in a lawn-and-garden tool, the combination of a housing having a longitudinal axis and further having respective side portions. Each of the respective side portions has an opening formed therein generally parallel to the longitudinal axis of the housing. At least one slide-in rechargeable battery pack is removably received in each of the openings in the housing, such that the housing is balanced. A permanent magnet motor is disposed within the housing and selectively energized by the battery packs. A plurality of planetary gear systems are driven by the motor and arranged in cascade in the housing. An output shaft is powered by the planetary gear systems, the output shaft having a relatively-low output speed and, conversely, a relatively-high output torque. A tool implement is disposed externally of the housing and driven by the output shaft.
In another aspect of the present invention, there is disclosed a tool having a drive means having a motor. A gear system having a plurality of planetary gear is driven by the motor. A single ring gear engages the plurality of planetary gears.
These and other objects of the present invention will become apparent from a reading of the following specification taken in conjunction with the enclosed drawings.